Safety belt buckle and inertia restraint adapter therefor



Dec. 5, 1961 E. PRETE, JR 3,011,237

SAFETY BELT BUCKLE AND INERTIA RESTRAINT ADAPTER THEREFOR Filed Dec. 27. 1955 mam-l1.

ERNEST HPETE, JR.

IN V EN TOR.

Sta

rent

The present invention relates generally to improvements in, safety belt buckles, and is more particularly concerned with a structure which will prevent inertia loads acting on the free end of a strap associated with the buckle in such a manner as to actuate the buckle inadvertently and release the strap.

Investigation and analysis of aviation and automobile crash accidents has revealed the possibility of belt slippage and inadvertent release of safety belts as presently constructed, due to inertia loads causing a whipping action of the free end of the belt webbing, and by actuating the buckle so as to release the lift latch, when the belt is worn loosely adjusted.

Having in mind the foregoing, it is one object of the herein described invention to provide a safety belt buckle, wherein the inertia loads on the free end of the belt will be rendered ineffectual to cause slippage or release of the buckle.

A further object is to provide an inertia load restraint attachment as a separate article of manufacture, which may be applied to existing buckle constructions.

Further objects of the invention will be brought out in the following part of the specification, wherein detailed description is for the purpose of fully disclosing the invention without placing limitations thereon.

Referring to the accompanying drawings, which are for illustrative purposes only: Y

FIG. 1 is a plan view of a safety buckle embodying the herein described invention;

' FIG. 2 is a side elevational view of the same;

' ture; and

FIG. 5 is a side elevational View of the same as seen from the line 55 of FIG. 4. I t

As more specifically shown in the drawings, the buckle of the present invention comprises a frame which is deformed or otherwise fabricated to provide spaced side flanges 11 and 12 connected together by a crosspi'e'ce 13.

As more clearlyshown in FIG. 2, each side flange consists of an upstanding portion in which peripheral edges 14 and 15 angularly converge and are joined by an arcuate edge 16 at the highest point of the side flange. This portion of the side flange is provided with an opening 17 in each case, these openings being adapted to receive the opposite ends of a cross-shaft or pivot pin 18 which provides a pivotal support for a clamping member as generally indicated by the numeral 19 in FIG. 3.

The clamping member 1% is constructed with an enlarged end 20 and an integrally formed projecting tongue Positioned generally below'the camming surface 23 is a raised portion in the crosspiece 13, which forms a platform or pad.25, the upper surface 26 of which forms an abutment surface confronting the serrations 24 and cooperable therewith to clampingly engage the end of a strap of flexible webbing or other material positioned over the surface 26 under the serrations, Thep'ad 26 is upwardly curved betweenthe sideflanges' 11 and12 so that the central portion "of the pad is higher. than .the portions adjacent the side flanges. This construction is especially advantageous in that, when pressure is applied against'the strap, the central portion is deflexed .downwardly so that there is a tendency to form a planar abutment surface extending throughout the pad length, and 7 thus uniformly grip the strap throughout its entire width;

In conventional constructions, where the abutment sur-J face, which cooperates with the cam serrations, is of planar configuration initially, thegrippingforces deflect the central portion of the pad in sucha way that the gripping action on the strap is confined substantially to the marginal edges'and an inefiiciently operating buckle is obtained. Y I Underlying the. tongue or handle 21, the crosspiece is provided with a slot 27 which forms at this end of the crosspiece a crossbar 28 which may be utilized as an anchor connection for a looped end 29 of a strap which may thus be anchored and secured to the buckle. The running end of this strap or a difierent strap, as indicated by the numeral 30', which is to be releasably connected with the buckle, is inserted over the crosspiece 13 under the camming surface serrations, and thence passing under the tongue or handle 21 with thefree end projecting beyond the buckle. The camming surface serrations and the handle 21 are biased towards the position shown in full lines in FIG. 3, wherein the serrations are in gripping position withrespect to the associatedstrapend.

A buckleof the foregoing construction forms an effective releasable connector for use in connection with safety belts and the like, when operating under normal conditions. It has been revealed, however, from investigations and analysis of aviation and automobile crash accidents that strap slippage and inadvertent release of the buckle may be caused under abnormal conditions due to inertialoads causing a whipping action of the free end of the strap, and by the tendency to release the lift latch in certain types of buckles, when the belt is Worn loosely adjusted.

It is one of the'features of the present inventiontoseparately constructed as a separate article of manufacture in the form of an attachment, as shown in FIGS. 4 and 5, which may be applied to an existing buckle.

As shown, the shield is of unitary construction and includes spaced side flanges 32 and 33, each of these side flanges being provided with an opening 34 which are aligned to receive therethrough the pivot pin 13 of the buckle and thus form a hinge for the shield structure, the side flanges in assembled position in the buckle being;

respectively positioned between the end of the enlarged end 20 and theadjacent side flange of the frame 10.

The other ends of the side flanges 32 and 33 are interconnected by a bridging bar portion 35. The edge of the bar on the same side as the projecting end flanges 32 and 33 is deflected to form an angularly extending marginal edge portion 36. On the opposite side of the bar 35, there is formed a laterally extending tongue-like projecs ims? Patented Dec. 5, 1961 tion 37 which may be constructed with a solid surface or may be provided with a cutout opening 38, as shown, to lighten the finished product.

In the assembled position of the shield structure on the buckle, it is proposed to provide for slight pivotal movement of the shield about the pivot pin on which it is mounted, in order to facilitate threading of the belt through the buckle. However, the pivotal movement of the shield in a direction toward the handle 21 should be limited in order to prevent the shield from striking the handle and thus transmit the inertia load to the handle.

Limited movement of the shield structure is obtained by,

providing on one of the side flanges a projecting portion 39 on the side flange 32 adjacent the opening 34 therein. This projecting portion 39, as shown in FIG. 3, is adapted, upon slight swinging movement of the shield structure in a counterclockwise direction, to strike against the adjacent portion of the crosspiece 13 so as to limit the swinging movement of the shield structure.

Various modificationsmay suggest themselves to those skilled in the art without departing from the spirit of the invention, and,'hence, I do not wish to be restricted to the specific form shown or uses mentioned, except to the extent indicated in the appended claims.

I claim:

1. In a belt buckle, the combination comprising: a frame; a cam member supported on said frame for movement to gripping and nongripping positions with respect to a flexible strap member passed between said cam and an adjacent part of said frame; means biasing said cam member to gripping position; a handle for manually actuating said cam member to nongripping position, said handle in the gripping position of said cam extending over a free end of the flexible strap; a shield member interposed between said handle and strap free end; and means swingably attaching said shield to said frame for loose riding engagement with the strap free end, but limiting said swinging movement short of engagement with said handle in said gripping position of said cam, whereby movement of the cam to nongripping position, due to handle movement by inertialoads acting on the free end of the strap, is prevented.

2. In, a belt buckle, the combination comprising: a frame; a cam member; a pivot pin supporting said cam member on said frame for movement to gripping and nongripping positions with respect to a flexible strap member passed between said cam and an adjacent part of said frame; means biasing said cam member to gripping position; a handle for manually actuating said cam member to nongripping position, said handle extending over a free end of the flexible strap; and a shield member supported on said pivot pin and limited. for swinging movement in the direction in which said handle is moved to release said strap, and having a part extending between said handle and strap free end, whereby movement of the cam to nongripping position, due to handle movement by inertia loads acting on the free end of the strap, is prevented.

3. In a belt buckle, the combination comprising: a frame; a cam member; a pivot pin supporting said cam member on said frame for movement to gripping and nongripping positions with respect to a flexible strap member passed between said cam and an adjacent part of said frame; means biasing said cam member to gripping position; a handle for manually actuating said cam member to nongripping position, said handle extending 'over a free end of the flexible strap; a shield member having side flanges containing apertures for receiving 4 said pivot pin therethrough, said shield member having a part extending between said handle and strap free end limited in its direction of movement towards said handle, whereby movement of the cam to nongripping position, due to handle movement by inertia loads acting on the free end of the strap, is prevented.

4. In a belt buckle, the combination comprising: a frame; a cam member; a pivot pin supporting said cam member on said frame for movement to gripping and nongripping positions with respect to aflexible strap member passed between said "cam and an adjacent part of said frame; means biasing said cam member to gripping position; a handle for manually actuating said cam member to nongripping position, said handle extending over a free end of the flexible strap; a shield member having side flanges containing apertures for receiving said pivot pin therethrough to support the shield member for pivoted movement, one of said side flanges having a projection engageable with a part of said frame to limit pivotal movement of the shield member in one direction, and said shield member having a part extending between said handle and strap free end, whereby movement of the cam to nongripping position, due to handle movement by inertia loads acting on the free end of the strap, is pre vented. v

5. As an article of manufacture, an attachment for a belt buckle having a handle actuated cam swingably mounted on a pivot pin, which acts to prevent movement of the cam to a release position with respect to an engaged strap as a result of handle movement under the action of inertia loads on the free end of the strap, comprisingz a pair of spaced side flanges, each having an opening at one end, said opening being aligned and adapted to re ceive a pivot pin therethrough; a bar portion connecting the other ends of said side flanges; a laterally extending tongue-like projection extending from said bar on a side thereof opposite that on which said flanges are positioned; and a projecting abutment portion on the end of one of said side flanges adjacent the opening formed therein.

6. A safety belt buckle comprising a base plate, opposite upstanding side flanges carried thereby, means adja' cent to one end of the plate for attaching a belt end thereto, a gripping jaw bar disposed across the base plate adjacent to the other end thereof, means pivotally sup-.

porting said jaw bar at its ends for rocking movement on an eccentric axis which is in fixed relationship to the base plate for effecting the clamping of an end portion of a belt against the base, an actuating lever for and carried by said bar and extending toward said one end of the plate when the bar is in clamping position, a restrainer plate between said side flanges in spaced relation with the base plate and interposed between the latter and said lever and having a flat belt engaging portion, an end of said restrainer plate being relatively close to said jaw bar, and means adjacent to said end of said restrainer plate coupling the latter to said flanges for limited rocking movement on a transverse axis for preventing engagement of said restrainer plate with said lever.

References Cited in the file of this patent UNITED STATES PATENTS 1,651,435 Bernstein Dec. 6, 1927 1,716,440 Heberling June 11, 1929 2,517,424 Griswold Aug. 1, 1950 FOREIGN PATENTS 4,274 Great Britain 1910 13,134 Great Britain 1909 

